Many people love chocolate, but while some people prefer milk chocolate, others reach for the darkest chocolate they can find. While some people consider very dark chocolate flavor to be somewhat bitter in comparison to a sweeter milk chocolate bar, others prefer the taste and perhaps the added health benefits.

You’ve probably heard that dark chocolate is better for you than milk chocolate. According to Healthline, that can be true because chocolate that contains between 70-85% cocoa also includes antioxidants, extra fiber and minerals such as potassium and magnesium. In addition, it might improve blood flow and reduce the risk of high cholesterol.

While all of that sounds great, it turns out that some dark chocolate also includes some potentially dangerous ingredients. A Consumer Reports study discovered that some brands of dark chocolate contain unsafe levels of lead, cadmium or both.

A lot of dark chocolate contains a little bit of lead and cadmium, so in order to determine if the amount was truly unsafe, Consumer Reports used California’s maximum allowable dose level (MADL). If a product contained more than 100% of the MADL, it was deemed unsafe.

Here is a list of 5 brands of dark chocolate that contain high levels of lead or cadmium:

1. Dove Promises Deeper Dark Chocolate 70% Cacao
2. Godiva Signature Dark Chocolate 72% Cacao
3. Hershey’s Special Dark Mildly Sweet Chocolate
4. Lindt Excellence Dark Chocolate 85% Cocoa and Lindt Excellence Dark Chocolate 70% Cocoa
5. Trader Joe’s Dark Chocolate 72% Cacao and Trader Joe’s The Dark Chocolate Lover’s Chocolate 85% Cacao

For the study, Consumer Reports tested 28 different chocolate bars. While the bars listed above were some of the worst offenders, they also discovered the bars that are the safest to eat. Here are the brands that made the safe list:

1. Ghirardelli Intense Dark Chocolate86% Cacao and Ghirardelli Intense Dark Chocolate Twilight Delight72% Cacao
2. Mast Organic Dark Chocolate80% Cocoa
3. Taza Chocolate Organic Deliciously Dark Chocolate70% Cacao
4. Valrhona Abinao Dark Chocolate85% Cacao

There were many other bars that fell somewhere in between, falling on the unsafe list for either lead or cadmium. If you’re a true dark chocolate lover, it’s safest to reach for a bar made by Ghirardelli, Mast, Taza or Valrhona. Otherwise, it’s safer to choose a bar that has a lower cocoa content.

Toxicologist Michael J. DiBartolomeis, PhD, is a former official at the California Department of Public Health, and he has researched heavy metals in chocolate. He believes pregnant woman and children should avoid eating dark chocolate, but for everyone else, it’s good to know the risks and only eat it sparingly.

Does it surprise you that some dark chocolate actually contains unsafe levels of lead and cadmium? What’s your favorite kind of chocolate?